Discriminating device for shuttleless coil-winding machines of closed cores

ABSTRACT

A discriminating device for selecting and assisting in the removal of successive convolutions of wire from a wire bundle drivingly supported on a pair of spaced rollers to dispose one run of the wire bundle through the opening of a toroidal core on which the wire is to be wound. The discriminating device includes an arm defining an upper guide edge extending to a point adjacent to the core but just below the plane of the wire bundle. A cam driven in timed relation to the other components of the device periodically raises the arm to a position wherein the edge thereof moves between the wire strand being wound and the remaining convolutins of the wire bundle to lift the wire stand being applied to the core so that a pickup roller driven in timed relation to the arm elevating cam can pull a fresh loop of wire from the bundle to permit continued winding. The loop of wire passes through tensioning means adjacent to the core as thw wire is wound.

United States Patent 72] Inventor Frontlsek Jagos Prague, Czechoslovakia [21 Appl. No. 23,408

[22] Filed Mer- 27, 1970 l 45 Patented Nov. 23, 1971 l 73] Assignee Tesla, nerodnl podnlk Prlho, Czechoslovakia [54] DISCRIMINATING DEVICE FOR SHUTTLELESS COIL-WINDING MACHINES OF CLOSED CORES FOREIGN PATENTS 911,622 11/1962 Great Britain ABSTRACT: A discriminating device for selecting and assisting in the removal of successive convolutions of wire from a wire bundle drivingly supported on a pair of spaced rollers to dispose one run of the wire bundle through the opening of a toroidal core on which the wire is to be wound. The discriminating device includes an arm defining an upper guide edge extending to a point adjacent to the core but just below the plane of the wire bundle. A cam driven in timed relation to the other components of the device periodically raises the arm to a position wherein the edge thereof moves between the wire strand being wound and the remaining convolutins of the wire bundle to lift the wire stand being applied to the core so that a pickup roller driven in timed relation to the arm elevating cam can pull a fresh loop of wire from the bundle to permit continued winding. The loop of wire passes through tensioning means adjacent to the core as thw wire is wound.

g I 'III/IIIIAIVI/III/A PATENTEnuuv 23 I97! 3. 622 O92 SHEETIUFZ Willa-711111 INVENI'OR. FRm/T/seK J RG05 DISCRIMINATING DEVICE FOR SI-IU'I'I'LELESS COIL- WINDING MACHINES OF CLOSED CORES 1 BACKGROUND OF THE INVENTION This invention relates to a discriminating device for shuttleless coil-winding machines particularly designed for winding of coils on closed cores of toroidal or rectangular shape and of miniature size. Similar closed cores are frequently used in electronic logic and impulse circuits.

1 Known coil-winding machines of this type, as disclosed for instance in the Us. Pat. No. 2,978,l93 or in the British Pat. No. 911,622 use a conductor long enough to produce the desired coil, which is prior to the proper winding of the coil wound on two supporting rollers, located outside the core, forming a skein from this conductor, one side of which skein passes through the opening of the closed core, on which the coil has to be wound, whereas the other side of the skein remains outside the core. One end of the conductor is fixed and a pickup roller performing a combined track consisting substantially of two elliptic parts engages a single conductor from the skein, causing its pulling off, first from one supporting roller and subsequently from the second supporting roller fonning thus one turn on the core which turn is tightened by a pull of the skein produced by the supporting rollers. The length of the conductor for one turn on the core is a fraction of the length of one skein turn and a relatively large number of turns may be wound on the core from a small number of turns in the skein so that when starting the winding of the closed core, only a few conductors of the skein have to pass through the opening of the core.

In order that the pickup roller can engage the proper conductor from the skein, a discriminating device is used, which separates always the proper conductor which has to be used for forming the subsequent coil turn. A properly bent steel wire is for instance used for this purpose according to the British Pat. No. 91 1,622 which wire passes through the opening of the core. A drawback of this arrangement is, that this discriminating wire reduces the opening of the core and limits particularly for very small cores the number of turns of the conductor which can be wound on the core. This drawback is particularly embarrassing when winding microtoroid cores having a small internal diameter. According to another solution which is object of the U.S. Pat. No. 2,978,193 a tooth on one of the supporting rollers engages one conductor of the skein and passes it over to a specially shaped through, over which the conductor slides to be finally also pulled off from the second supporting roller. This apparently simple solution has the drawback, that the conductor is in the course of winding and tightening of a turn subject to substantial stresses due to the resistance offered by the surfaces over which the conductor has to slide, so that it is rather difficult to use this method for winding of fragile conductors of small cross section.

SUMMARY OF THE INVENTION It is an object of this invention to provide a discriminating device for this purpose which would leave the core opening free for the coil turns.

It is a further object of this invention to enable a smooth taking over of the conductor by the pickup roller from the skein.

It is a still further object to enable to utilize the utmost of the core space for the coil turns.

A still further object of the invention is to reduce to the utmost any stresses of the conductor in the course of winding.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows the main parts of the discriminating device together with parts of the winding machine in elevation.

FIG. 2 is a top view.

DESCRIPTION OF PREFERRED EMBODIMENT Several loops of an insulated conductor fonning a skein l is prewound on supporting rollers 3 and 4, one of which rollers, the roller 3 is a driving roller, the second roller 4 a springloaded tensioning roller. One side of this skein 1 passes through the center of a closed core 2 whereas the other side of the skein remains outside the core 2. The driving roller 3 is provided with a groove 12 of suitable shape to prevent any 0 twisting of the individual turns of the skein l. The operating part 5 of the skein 1 forms in the course of operation the individual turns of the coil on the core 2 so that after prewinding of the skein 1 from a supply spool on the supporting rollers 3 and 4, the end of the conductor is clamped in a holder 6, securing thus the start of the first and subsequently of each following turn. An angle a is created between the operating part 5 of the conductor and between the skein l passing through the opening of the core 2, and after clamping the end of the conductor in a tensioned state in the holder 6, the conductor rests against the internal edge of the closed core 2. This angle a is smaller if cores with smaller internal dimensions are wound. The extremity of the edge 8 of a discriminating arm 7 extends approximately into the center of this angle a, the vertical and horizontal position of which arm 7 can be adjusted in its inoperative position for instance by means of the screw 14, as illustrated in FIG. 1 and 2, to remain in its inoperative position always below the horizontal plane of the skein part, passing through the core 2.

The other end of the discriminating arm 7 is provided with a rounded extension 9 for engaging the operating part 5 of the conductor and for its transfer to a pickup roller 1]. Cam means 16 transmit to the arm 7 fixed on a mandrel 13 a reciprocating up and down movement once in the course of each cycle completing one turn on the core 2. A rounded adjustable arm I0 secures the proper position of the wound conductor and prevents due to its rounded shape the breaking of the conductor. A pickup roller 11 easily rotatable around its axis, performing a movement along a track indicated in FIG. 2 by a dash and dot line and composed substantially of a combination of two elliptic tracks, is adapted to engage the conductor singled out by the discriminating device. The movement of the pickup roller 11 can be derived as is for instance indicated in the British Pat. No. 91 1,622 from two cranks, to the extremity of which is linked an arm supporting the pickup roller II. One crank rotates uniformly, the other crank periodically swings in one and the other direction due to a periodically changing one way coupling in one and in the other direction. For suitably chosen relations of the individual elements a track as indicated in FIG. 2 can be obtained, composed substantially of two elliptic tracks. The movements of the pickup roller 11 and of the discriminating arm 7 are synchronized and derived advantageously from a common drive.

Deviations of the angular adjustment of the extremity of the edge 8 of the discriminating arm in the course of its up and down movement are eliminated by a spring I5 which rests against an edge of the discriminating arm 7.

A depositing device is provided in front of the core 2 composed of two jaws 21 and 22, each having a straight portion pressed against the straight portion of the other jaw by a spring 23, the pressure of which is adjustable. The jaws 21 and 22 provide substantially around their whole circumference a guiding surface 4 for the conductor which enters at one side between the jaws 21 and 22 to be pulled off on the other side in the course of tightening of the just wound turn on the core 2.

Let us suppose that a coil has to be wound on a microtoroid core 2. The core 2 is placed for instance on two flanged rollers, with a spring-loaded third flanged roller securing the proper position of the core 2. Several loops of a conductor are wound on the supporting rollers 3 and 4 forming a skein 1, one side of which passes through the center of the core 2. One end of the conductor is clamped in the holder 6, whereby the operating part 5 of the conductor rests against the internal edge of the core 2 and forms an angle a with the skein l. The extremity of the edge 8 of the discriminating arm 7 is adjusted approximately to the center of the angle a, close to the adjustable arm and below the plane of the skein l. The rounded part 9 is beyond the angle a. In the position indicated in FIG. 2 by a dashed line, the discriminating arm 7 has been raised by the cam means 16 and has singled out the operating part 5 of the skein 1, whereby the conductor has slid along the edge 8 to the rounded extension 9 to be taken over by the pickup roller H in its position marked in FIG. 2 by 19 which subsequently pulls the conductor first from the supporting roller 3, passes through position 18 and proceeds towards the roller 4, to pull subsequently the conductor also off the supporting roller 4. The discriminating arm 7 is in the course of this operation lowered into its inoperative position below the plane of the skein 1. The skein 1 is during this operation driven by the supporting roller 3 over a friction coupling so as to keep the conductor permanently tensioned. When the pickup roller 11 pulls the conductor from the supporting roller 4, the conductor enters between the jaws 21 and 22 of the depositing device 17, where the conductor is clamped and simultaneously in the position marked by 20 pulled off the pickup roller 11. The pickup roller 11 subsequently proceeds to position 18 and again back to position 19 to start a new winding cycle.

The conductor is in the meantime guided between the jaws 21 and 22 before completion of the turn, which jaws 21 and 22 are elastically pressed one to the other and finally pulled off the jaws 21 and 22 to be deposited at the proper place of the core 2. Thus one turn is wound, the core 2 is turned around its axis for a small angle corresponding to the thickness of one conductor and a new winding cycle can start.

The discriminating device according to this invention leaves the opening of the core free for the wound conductor, it engages the conductor smoothly and transfers it without undue bending and stresses to the pickup roller, so that it is rather advantageous for winding of coils on closed cores of miniature size, using conductors of small cross section.

I claim:

I. A discriminating device for selecting a conductor from a skein for shuttleless coil-winding machines of closed cores, where a skein to be wound on the core is stored on a couple of supporting rollers, whereby one side of the skein passes through the opening of the core, with a pickup roller cyclically engaging the operating part of the wound on conductor,

said discriminating device comprising an ann extending into a guiding edge, the extremity of said edge situated close to a face of the core being wound, means for periodically raising and lowering said discriminating device in dependence on the cyclical movement of the pickup roller so that the extremity of the edge of the arm passes close to the face of said core, situated in its raised position within an angle formed between the wound conductor and the skein part passing through the closed core and being in its lowered position beyond the plane of the skein,

an extension provided on said arm situated distant from the face of the core and beyond the angle formed between the wound conductor and the skein part passing through the core, to transfer the conductor singled out by the extremity of the guiding edge in its raised position to said pickup roller.

2. A discriminating device as claimed in claim 1 comprising means for adjusting the position of the extremity of the guiding edge with respect to the operating part of the wound on conductor. 

1. A discriminating device for selecting a conductor from a skein for shuttleless coil-winding machines of closed cores, where a skein to be wound on the core is stored on a couple of supporting rollers, whereby one side of the skein passes through the opening of the core, with a pickup roller cyclically engaging the operating part of the wound on conductor, said discriminating device comprising an arm extending into a guiding edge, the extremity of said edge situated close to a face of the core being wound, means for periodically raising and lowering said discriminating device in dependence on the cyclical movement of the pickup roller so that the extremity of the edge of the arm passes close to the face of said core, situated in its raised position within an angle formed between the wound conductor and the skein part passing through the closed core and being in its lowered position beyond the plane of the skein, an extension provided on said arm situated distant from the face of the core and beyond the angle formed between the wound conductor and the skein part passing through the core, to transfer the conductor singled out by the extremity of the guiding edge in its raised position to said pickup roller.
 2. A discriminating device as claimed in claim 1 comprising means for adjusting the position of the extremity of the guiding edge with respect to the operating part of the wound on conductor. 